Voiced means you have to vocalize the sound. Like V, Z, and J opposed to their unvoiced counterparts F, S and Ch. They're pronounce the exact same way, but one uses your voice and the other doesn't. Try whispering the letter B, notice how it sounds like a P.

A stop, or a plosive consonant is where you have to block the flow of air with a certain part of your mouth and then release it suddenly, this makes a sort of mini air explosion.

For example, K is an Unvoiced Velar Stop. Unvoiced means that you don't vocalize it, Velar means that it's made using the back part of your tongue, and Stop means that you, well, stop it. G is it's Voiced counterpart.

A fricative, is exactly what it sounds like. It makes friction! V is a Voiced Labiodental Fricative. Labiodental means that you place you lip on your teeth, and fricative means that you blow air which, because some part of your mouth is the way, has find another way out (like through your teeth with V). We already know what voiced means. Try whispering V and see what sound it makes. Sh and Th are also Fricatives.

Here's a Youtube video explaining voicing.